John linkert



(No Model.)

' J. LINKERT.

I ARTIFICIAL FOOT. No. 468,352. Patented Feb. 9, 1892.

UNITED STATES PATENT OFFICE.

JOHN LINKERT, OF HAMILTON, OANADA, ASSIGNOR OF ONE-HALF TO HENRY ARLAND, OF SAME PLACE.

ARTIFICIAL FOOT.

SPECIFICATION forming part of Letters Patent No. 468,352, dated February 9, 1892.

Application filed August 10, 1891- Serial No. 402,322. (No model.)

To all w/mm it 11mg concern.-

Be it known that I, JOHN LINKERT, a subject of the Queen of Great Britain, residing at the city of Hamilton, in the county of IVentworth, in the Province of Ontario and Dominion of Canada, have invented certain new and useful Improvements in Artificial Feet; and I do hereby declare that the following is a full, clear, and exact description of IO the same.

My invention relates to certain new and useful improvements in artificial feet, the object being to extend shortened legs and feet to full length and to so construct the same that they shall appear and act and be adapted to be used as are the natural feet in walking.

My invention consists in the construction of an artificial foot consisting of several parts, all combined together, as hereinafter described, and adapted to take and imitate the motions and to be used as natural feet are, extending the limb as necessary, the whole to be fixed in and covered by a boot, the lower and exposed portions of which shall have the 2 5 ordinary and natural appearance. The boot is an essential part of the device, as the natural foot and extension foot require it to assist in keeping them firmly together, as well as to protect device from wearing unduly.

Reference is made to the accompanying drawings, in which- Figure 1 is a plan of the device divested of the boot portion. Fig. 2 is a bottom view of the same. Fig. 3 is a vertical longitudinal 3 5 section on line 00 as of Fig. 1. Fig. 4 is a side elevation of the boot. Fig. 5 is the device bent.

Similar letters refer to similar parts in all the figures.

In the drawings, A represents the heelpiece, B is the instep-piece, C is the ball-piece, and D the toe-piece. The heel-piece A is made somewhat in the form of the heel portion of a last. It is attached to the insteppiece 13 at its upper edge by two straps F F,

which are securely fastened to' the parts A and B.

To prevent the pressure on the part B from shoving it downward with respect to the piece A, a strap G is firmly attached to B at its rear part and brought up between B and A and firmly secured to the latter.

A spiral spring II is inserted in the opening between the pieces Aand B near the bottom, as shown. Its use is to regulate the motion of the parts. The instep-piece B is likewise attached to the ball-piece O firmly by a strap F firmly attached to both these parts.

There is a strap G firmly fixed to the forward end of the part B and turned over fiat and secured on the top of the piece 0. This is to prevent the ball-piece C from shoving up when the instep-piece B is pressed downward. It is provided with a toe projection and a toe-cap K to retain the toes in the de- 6 vice.

The toe-piece D is attached to the ball-piece O by the strap F on the under side. The opening between the pieces 0 and D is made V-shaped, so as to allow the toe-piece D to bend 7c upward. The strap G is firmly attached to both parts to prevent D from bending downward.

There are two spiral springs H H placed between the parts D and C. These are for the purpose of keeping the toe-piece D down when it is bearing no pressure.

The toe-piece D has a cap M, of strong leather, as shown. This cap slides up and down on the cap K when the toe-piece D moves up or down. It assists in making a natural wrinkle in the upper of the boot at the joint between C and D when the parts are bending.

The strap J is firmly attached to the heelpiece A and the ball-piece O. This serves to keep the device the same length whether it is bent or straight.

The partB has a wire loop L, through which the strap J passes freely. This serves to keep 0 it near to the part B and prevents it from sagging down.

The parts A, B, C, and D so arranged and with their accessory parts already described are to be secured in a suitable covering, pref- 5 erably of leather. This serves to prevent undue wear and does not allow foreign substances to get in between the parts.

The whole is to be put into a boot into which it will neatly fit. It is to be firmly I00 fastened into the boot by a screw S running up through the heel of the boot and the heelpiece A oftthe device, as shown in Fig. 3.

There is a, ridge R. in the upper forward part of the instep-piece B. The ball of the foot rests in this and takes some portion of the pressure of the foot. The foot can now be inserted in the device and the retainingstrap 0 buckled over the upper part of the instep of the foot. This must be tight enough to bear the greater part of the weight of the body,leaving but little weight on the ball of the foot and none on the toes. The boot can now be laced up securely. By resting the foot with the device on the floor it will be in its normal position, as shown in Fig. 3. Now raise the other foot and step forward. This will raise the heel-piece A off the ground and elevate the rear portion of the instep-piece B. This has the effect of bending the ballpiece C- upward. This will pry open the space between the parts B and O at the bottom, when the strap J will bring the heel-piece A the same distance forward, thus keeping a constant length of foot. As the body continues to move forward, the heel-piece A and instep-piece B are raised still higher, and the rear part of the ball-piece C will be elevated. This will have the eifect of bending the toepieee D upward. The step is now completed and the other foot is firmly planted on the ground and taking pressure.

In the act of lifting the foot with the device ott the ground the toe-piece Dis pushed back to its normal position by the spiral springs H H At the same time the heelpiece A is pushed away from the instep-piece B by the spiral spring A, and the strap J pulls the ball-piece G into its normal position. (See Figs. 3 and 5.)

Having thus fully described my invention, What I claim, and desire to secure by Letters Patent, is

In an artificial foot, the combination, with the heel-piece A and ball-piece G, of the strap J, spiral spring H, straps F F G, instep-piece B, straps F G ,toe-piece D, straps F G spiral springs H H and cap K, substantially as and for the purposes hereinbefore set forth.

Hamilton, Canada, August 5, 1891.

' JOHN LINKERT.

Witnesses: V

PATK. ARLAND, CYRUS CARROLL. 

